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Scrubbers

Expert replies
by dkumar.83 » Sun Jun 27, 2010 10:58 am
Installing scrubbers in smokestacks and switching to cleaner-burning fuel are the two methods available to Northern Power for reducing harmful emissions from its plants. Scrubbers will reduce harmful emissions more than cleaner-burning fuels will. Therefore, by installing scrubbers, Northern Power will be doing the most that can be done to reduce harmful emissions from its plants.
Which of the following is an assumption on which the argument depends?
(A) Switching to cleaner-burning fuel will not be more expensive than installing scrubbers.
(B) Northern Power can choose from among various kinds of scrubbers, some of which are more effective than others.
(C) Northern Power is not necessarily committed to reducing harmful emissions from its plants.
(D) Harmful emissions from Northern Power’s plants cannot be reduced more by using both methods together than by the installation of scrubbers alone.
(E) Aside from harmful emissions from the smokestacks of its plants, the activities of Northern Power do not cause significant air pollution.
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Source: — Critical Reasoning |

by sk818020 » Sun Jun 27, 2010 11:01 am
The answer is D.

Try negating it and testing. Emissions can be reduced more by using both methods together. Could the author then conclude that by installing the scrubbers Northern Power will be doing the most to reduce harmful emissions. No, because both ways combined would be more effective. Thus, the author is assuming D.

Could you please confirm the OA is D.

Hope this helps.

Thanks,

Jared
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by dkumar.83 » Sun Jun 27, 2010 11:06 am
You are right, but why not E?
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by FightWithGMAT » Sun Jun 27, 2010 11:19 am
dkumar.83 wrote:You are right, but why not E?
Conclusion says that installing scrubber alone is the best available method. There is no other option or combination better than this. D is being assumed to reach this conclusion.

B could be second best option, but argument does not talk about the selection of scrubbers among the available kinds of scrubbers in the market.
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by sk818020 » Sun Jun 27, 2010 11:24 am
From the passage we don't know if northern power has other areas of its operations that cause significant air pollution. If the company does have other areas of its operations, we also are not told how much they pollute and whether there can be anything done about it. This is the reason E is not assumed in the argument.

E is irrelevant because it doesn't change the fact that installing the scrubbers could still be the most effective way to decrease emissions, even if there were other areas of the company that caused pollution.

Hope this helps.

Thanks,

Jared
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